1. Choosing the right statistical test for the problem
What test when?
Choosing the right statistical test for the problem

2. Is there a difference between means?

3. Is there a difference between means?

4. Is there an association between variables?
should be “2 or more”

5. Someone is curious to find out the long term effect of premature birth is on mental development. He goes to a large school district, gets a sample of sixth graders, and finds out each student’s IQ score. From each student’s parents he finds out if the student was full-term or premature. What statistical test should he do to find if there if premature birth effects IQ?
Someone is curious to find out what the long-term effect of premature birth is on mental development. He goes to a large school district, gets a sample of sixth graders, and finds out each students IQ score. From each student’s parents he finds out if the student were full-term or premature. What statistical test should he do to find if there is a relationship between prematurity and IQ?
two independent groups, comparing means using interval data
Comparing means, frequencies or relationship?
Measurement scale?
Independent t

6. A committee appointed by the American Nurses Association was charged with finding out whether the number of men becoming nurses has increased in the last ten years. They obtained a random sample of 35 schools of nursing and from each one found out the percentage of male graduates in 1996 and in What statistical test should they use to analyze these data?
Two dependent samples, ratio level dependent variable: dependent-samples t test/repeated-measures ANOVA
dependent t test

7. Chi-square for independence
A sample of students at a college was asked to classify themselves as: (1) Asian; (2) Black; (3) Hispanic; (4) Native American; (5) White; or (6) Other. Each person was also asked whether his or her family would consider it acceptable (yes or no) if he or she married someone in a different category. What statistical test should be used to see if the degree of acceptability differs among racial/ethnic categories?
frequencies, two or more independent samples: chi-square test for contingency tables (independence)
Chi-square for independence

8. What statistical test did I use to see if there was any difference in racial attitudes (using the RAS) among PT, PA and OT students?
one-way ANOVA and post-hoc tests

9. We divide the class randomly and give a cup of coffee to one group and decaf coffee the other half. We then give everybody a statistics quiz. What statistical test do we use to see if one group did better?
independent t test
independent t test

10. I want to know if our NBCOT mean score is any different from the national mean score.
z test (z ratio) p. 425
z test (either one-sample or normal deviate)

11. Chi- square goodness of fit
I want to know if our NBCOT pass rate is any different from the national pass rate.
Chi- square goodness of fit
Frequencies, Chi- square goodness of fit